Heat-insulating panel



P 23, 1930- B. R. ANDREWS 1,776,610

HEAT INSULATING PANEL Filed Feb. 1, 1930 lnvenTor.

Bernard R. Andrews- Alrys latentedsept. 23,1930 1,776,610 i UNITED. STATES PATENT,- OFFICE A pplicationflled February 1, 1930. Serial No. 425,136.

This invention relates to a heat-insulating the use to which it is to be put. In the panel which is suitable for use in building illustrated embodiment of the invention the walls of drying ovens,- drying chambers and panel is made longer than it is wide and similar devices, and especially to the soit is relatively thin compared to its length calledmetal panel which comprises a metal or width. In fact, I find that a panel of 55 envelope with the filling of heat insulating 1%" or 2" in thickness makes a practical material. and efficient panel.

When these panels are used there ismore In the drawings 1 indicates a panel emor less heat loss due to conduction or flow bodying my invention and this is formed of heat through the metal envelope from with an envelope 2 of sheet metal which cove0 the face of the panel which is exposed to ers the entire surface of the panel, the in a higher temperature and which presents a terior of the envelope being filled with some relatively 1211' e surface for picking up heat, suitable heat-insulating material 3 which to the face of the panel which is exposed to Will preferably be of a non-combustible char the atmosphere and which presentsa rela-- acter. I find that rock wool makes an ex- 65 tively large heat-radiating surface. cellent heat-insulating material but the in- It is the object of my present invention vention is in no way limited'to the'use of any to provide an improved metal panel in which particular material and hence I contemplate the heat loss is materially reduced and I using any appropriate heat-insulating ma- 1 accomplishthis by so making the envelope 'terial. I '7 of thepanel that it presents an area of' The envelope of the panel may be made reduced cross section adjacent the outer in any appropriate way without departing edge of the face of the panel which is subfrom the invention. In the particular conjected to a higher temperature. struction shown, said envelope is made with a The amount of heat which will be conthe two sections4 and 5, the section lhaving 7 ducted or. will flow through metal under any the upturned portions 6 which form the side given conditions isproportional to the cross edges of the completed panel and the mari sectional area of the metal and by forming ginal portions of which are bent over the the metal envelope with a zone of reduced flange 7 which is turnedup from each edge cross sectional area which is located adjacent of the section 5. This, however, is only. one so the outer edge of the face of the panel which way in which the metal panel may be conis subjected to a higher temperature, the structed. i v amount of heat which can flow or which will In using panels of this sort for building be conducted from said face to the oppbwalls of a drying oven the panels will prefersite face, which acts as a radiating surface, ably be placed edge to edge and supported will be correspondingly reduced. between and secured'to suitable posts or up- In order'to give an understanding of the rights and when the oven is in use one face invention I have illustrated in the drawings of each panel, for instance the face 8, will be a selected. embodiment" thereof which will subjected to the interior heat of the-drying 10 now be described after which the novel feaoven while the other face of each panel, for

tures will be pointed out in the appended instance the face-9, will be subjected to the claimstemperature of the surrounding atmosphere. Fig. l is a perspective .view of a panel In a panel of this type the heat-insulating embodying my invention; material 3 affords a practical heat insulation Fig. 2 is a perspective sectional view on against the conduction of heat directly from the line 2-2, Fig. 1; the heated face 8 of the panel to the nonlFig. 3 is a section on the line 3-3, heated face 9 thereof but the material of the a Fig. envelope at the edges 6 of the panel provides A panel embodyin my. invention may be a path through which heat may be conducted 60 made of any desira 1e size depending on from the heated surface8 of the panel, which provides a relatively large surface for picking up heat, to the non-heated surface 9 thereof, which constitutes a relatively large radiating surface. Any heat" which thus flows through the metal envelop'e from the heated pick-up, surface 8 to the radiating surface-9 represents a heat loss. In order to reduce this heat loss and thus make the panel a more effective heat insulator I propose to so form the envelope that it will present a zone of reduced cross sectional area adjacent, the outer boundary or portion of the heated face, and the presence of this zone ofreduced cross sectional" area interposes a barrierto the con duptionor flow of heat from oneface of the panel to the other and thus reduces the heat-loss occasioned by such flow.

The exact location of this zone of reduced cross sectional area is not important so long as it is in the vicinity or adjacent to the outer limits of the heated face. A convenient place to locate it is in the side edges 6 of the panel but it'might be in the outer marginal portion of either face 8 or 9 'and .yet be effective for the purpose desired. ThlS reduction in cross-sectional area may be obtained 1n various ways without departing from the invention. As one simple and practical method of obtaining this end I have shown the edge 'portion6 of the envelope-as provided with perforations 10, these perforations preferably being arranged in a row and thus coming in a zone encircling the panel. The presence of these perforations 10 reduces the total cross-sectional area of the metal in said zone. I find that it would be possible to place the perforations or apertures 10 at a distance approximately equal to the radius heat-insulating material 3 is concerned.

c of theenvelope for conducting heat from the of each perforation or even closer than this without inaterially weakening the envelope sovfar as its function as an envelope for the IVith thearrangement of perforations as above described at least two-thirds of the metal in the zone constituted by the row of perforations .is removed so that the total cross-sectional area of the envelope throughout the zone is only a third or less'than onethird of that at either side of said zone. 1

,The removal of any 'metal from the envelope reduces proportionately the capacity heated to the non-heated face of the panel and if it be assumed that the perforations are so arranged that in the zone approximmately three-fourths of the mass of metal has been removed from the edge walls6 then the capacity of these edge walls for conducting heat from the heated to the non-heated face of the panel will be correspondingly reduced, that is, redifced toone-quarter of what it would be without the presence of the apertures. V

The size and arrangement of the aper-.

times may be varied withoutaffecting the in vention in any way. Similarly the location of these apertures may be varied within limits without in any way changing the inventive idea so long as they are so placed that their presence reduces the conduction or flow tion in cross-sectional area inthe zone adjacent the outer marginal portion of the heated surface is formed in any other way would I come within my invention.

IVhere rock wool'or a similar heat-insulating material is employed within the envelope and the panels are ofcon'siderable size it may be desirable to provide some means within the panel for holding the heat-insulating material in place and evenly distributed. One simple way of accomplishing this is to provide a plurality of partitions 11 which extend across from one side to the other of the panel and which divide the interior of the, envelope into separate smaller compartments, each of which, of course, is

filled with the heat-insulating material.

These partitions may be formed of any suitable material apd they are herein shownas being retained ln place by bolts or rivets 12 extending through the sections 4 and 5 and through the partitions.

I claim:

1. A heat-insulating panel for use in building heat-insulated walls comprisinga metal envelope and a filling of heat-insulating material enclosed within said envelo c said envelope being formed with a zone adjacent the outer marginal portionsiof the face thereof which is subjected to heat in Which the total cross-sectional area of the metal of the envelope is considerably less-z-than that of the envelope adjacent said zone whereby the'capacity of the en'vel'ope to conduct heat from one face to the other of the panel is correspondingly reduced.-

2. A heat-insulating panel for use in build-. 1

ing heat-insulated walls, comprising a metal envelope and a filling of heat-insulating material enclosed within said envelope, the envelope being provided with closely arranged perforations in a zone adjacent the outer marginal portions of the face which is subjected to a higher temperatur' whereby the capacity of the envelope to con not heat from one face to the other is materially reduced.

In testimony whereof, I have signed my name to this specification.

BERNARD R. ANDREWS. 

